SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7080bf15b3faf05799a9fe2c72947a495881207fd1002b51b415f4835d86d8a9' 
  AND token = '41Siwnjsj+NtkJfK679L/jhivHVTzC4umIVd3xhqpw0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}